Nutrition Flashcards

Question

Phospholipids

Answer 1

majority of plasma membrane ◦ Modified triglycerides

Answer 2

is a precursor for steroid hormones, bile salts, vitamin D ◦ Required in the plasma membrane giving it flexibility ◦ Made in body and acquired in diet

Answer 3

Most structurally and functionally diverse ◦ Needed in adequate quantities to replace worn out protein structures ◦ Amount needed depends on age, sex, or overall health ◦ RDA: 45-60 grams / day

Answer 4

◦ 8 amino acids are essential meaning they must come from diet ◦ 12 amino acids are synthesized by the body ◦ AAs are not stored so they must be replenished regularly ◦ 4kcal energy / gram of protein

Answer 5

include all essential AAs (animal products)

Answer 6

– do not contain all essential AAs (plant proteins)

Answer 7

nitrogen (building block for DNA / RNA) – important! ◦ Nitrogen is excreted in urine if in excess ◦ Can be fatal if not high enough

Answer 8

Organic molecules required for metabolism ◦ Present in small amounts in food ◦ Water soluble or fat soluble ◦ Essential (must be absorbed from diet) or nonessential (produced as a byproduct of a chemical reaction)

Answer 9

include vitamin B and C ◦ Excess is secreted in urine

Answer 10

include vitamin A, D, E, K ◦ Absorbed from GI tract lacteals within micelles ◦ Excess stored in fat, may be toxic if taken in excess

Answer 11

Used in promoting eye health, precursor of visual pigment retinal

Answer 12

Helps keep nerve, muscle and blood cells healthy ◦ Required for the formation of DNA ◦ Coenzymes in chemical reactions ◦ Different types include biotin (B7), folate (B9), thiamine (B1) and more

Answer 13

Collagen formation, absorption of iron, growth / development / repair of body cells, serves as an antioxidant (along with A and K)

Answer 14

Forms calcitriol, increases calcium absorption from GI tract

Answer 15

Stabilizes and prevents damage to cell membranes

Answer 16

Required for synthesis of blood clotting proteins

Answer 17

Inorganic ions obtained from diet, some stored ◦ Required in daily amounts, all are essential and must be obtained from diet ◦ Can be major (>100mg/day required) or minor (<100mg/day required) ◦ Fortified – adding essential nutrients

Answer 18

in hemoglobin, binds oxygen; in mitochondria, in electron transport chain

Answer 19

required for the formation and maintenance of the skeleton, muscle contraction, blood clotting, exocytosis of neurotransmitters

Answer 20

maintaining a resting membrane potential in excitable cells, required to generate action potential

Answer 21

precursor for thyroid hormone

Answer 22

involved in protein synthesis and wound healing

Answer 23

United States Department of Agriculture’s (USDA) recommendation of desired proportions of food

Answer 24

Provide details on composition of prepackaged items

Answer 25

– Time eating, digesting, and absorbing nutrients – Lasts ~4 hours after a meal – Concentrations of glucose, triglycerides, and amino acids increased as absorbed from GI tract

Answer 26

maintains blood glucose levels (70 – 110 mg/Dl) * hormone released by pancreas when blood sugar is high – Stimulates liver and muscle cells to form glycogen – Stimulates lipogenesis and increases uptake of triglycerides from blood – Stimulates amino acid uptake accelerating protein synthesis

Answer 27

– Time between meals, body relying on stored nutrients, ~12 hours

Answer 28

maintains blood glucose levels * Regulatory hormone released from pancreas in response to decreased blood glucose levels – Stimulates liver to increase breakdown of glycogen to glucose – Gluconeogenesis from non-carbohydrate sources – Adipose tissue breakdown to triglycerides

Answer 29

occurs in hepatocytes – Fatty acids transported in blood enter hepatocytes » Synthesis depends on cholesterol intake Following its formation: ◦ Released into blood wrapped by a lipoprotein or ◦ Synthesized into bile salts as part of bile ◦ 90% of these reabsorbed while moving through ileum ◦ 10% lost in feces

Answer 30

deliver lipids from GI  liver, adipose, muscle (energy) – Formed in intestine from diet into lacteal

Answer 31

– Are associated with the transport of lipids from the liver  peripheral tissues * Lipids with a protein “wrap” for transport – Three types

Answer 32

Contain the most lipid lipid delivery vehicles  cells ◦ Various types of lipids + protein ◦ Assembled in liver and released into blood ◦ Transports triglycerides to peripheral tissue – especially adipose ◦ Releases triglyceride  becomes LDL

Answer 33

Less lipid cholesterol delivery vehicles  cells ◦ High amounts of cholesterol ◦ Bind to LDL receptors in plasma membrane of cell ◦ Engulfed by endocytosis ◦ Cholesterol incorporated into plasma membrane or used as a building block to produce steroid hormones

Answer 34

Least amount of lipid transport lipid from peripheral tissue > liver – Proteins formed in liver and released into blood – Circulate through blood and “fill” with lipids – Can make cholesterol available to steroid-producing tissue – Returned to liver and extra cholesterol is converted  bile salts

Answer 35

Carb metabolism protein metabloism lipid metabolism lipid transport

Answer 36

-Monossacharides absorbed from small intestine into blood and then enter the hepatocytes. Fructose and galactose are converted to glucose -Non-carbs converted to glucose via gluconeogenisis -Glucose > glycogen by glycogenisis and reverse by glycogenylysis

Answer 37

Deamination: amine group removed from amino acids. NH2 is converted to urea and urea enters the blood (eliminated by kidneys) Remaining elements oxydized in cell. resp. to generate ATP Amino acids used to form proteins and plasma proteins Transamination: amino acids converted from one form to another

Answer 38

Fatty acids joined with glycerol to form triglycerides (lipogenesis) Fatty acids removed from tryglyceride = lipolysis Fatty acid brake down into acetyl CoA (beta-oxidization) Acetyl CoA change to ketone bodies (water soluble molecules); ketone bodies released into blood, transported to other cells to be oxidized in cell resp. Acetyl CoA used in cholesterol synthesis: released into blood within VLDL's and some used to make bile salts and released as a component of bile.

Answer 39

Transport trygliceride and cholesterol (within VLDL's and LDL's) from liver to peripheral tissue empty HDL released to pick up lipids from tissues and blood and return as full HDL

Answer 40

Glycolysis Intermediate stage Citric acid cycle Electron transport system

Answer 41

* Anaerobic pathway in cytosol * 1 glucose > 2 pyruvate * 2 ATP formed

Answer 42

* Aerobic pathway in mitochondria * Pyruvate > Acetyl CoA * CO2 formed

Answer 43

Acetyl CoA > Citric acid

Answer 44

* Transferring of H+ and electrons from NADH and FADH2 * ATP formation through oxidative phosphorylation

Answer 45

changing macromolecule form

Answer 46

◦ Measure of energy used in a given period of time

Answer 47

◦ Amount of energy used a rest ◦ Measured with a calorimeter or a respirometer ◦ Varies due to age, lean body mass, sex, and hormone levels ◦ Decreases with age ◦ Thyroid hormone increases BMR ◦ Body surface area is important ◦ Greater surface of skin = greater heat lost ◦ Heat loss = cell energy required to make up for this

Answer 48

◦ BMR + physical activity ◦ Also influenced by environmental factors

Answer 49

◦ Variable heat produced due to variable metabolic rate ◦ Body temperatures maintained within certain physiological limits: 98.6⁰F neural and hormonal

Answer 50

mediated through hypothalamus ◦ Ex. Sweating / shivering / vasodilation ◦ Can initiate change in cortex (conscious) ◦ Ex. Behaviorally: put a coat on

Answer 51

mediated by thyroid hormone, epinephrine, growth hormone, and testosterone ◦ Thyroid hormone is the most significant ◦ Release signaled by hypothalamus increases the metabolic rate of cells

Answer 52

◦ Temperature to vital portions of they body kept relatively constant ◦ Maintained by fluctuating blood flow to peripheral regions